loose IEC power cord connection?

You may need some cable holders or elevators to keep the heavy or/and stiff power cord in place. I have two power cords like that and use improvised elevators. Unless things are really loose because either IEC is too big or power cord's plug too small by design, it should work.

I have used wood blocks under the bottoms of heavy A/C powercords. Or butyl rubber bottle stoppers.
Anso, (but messy) BluTack rolled out and pressed around the mating outer edge of the connection.
The messy part is when it it pulled apart. The Blutack stretches and is gooey.
I find I can clean it up using the Blutack to pick up itself until all is removed. Annoying but i do use Blutack like (cheap) stuff for antivibration control.

I also wrap the Female cord end of the IEC with Teflon plumbers' tape. About five or so turns makes the connection tight. (naturally if loose more, if already too tight, fewer)
Every one of my powercords also has the teflon tape on them.

I have improvised pc support using toilet tissue tubes. Cut a u shaped slot at one end, slip under the plug or IEC. Adjust
slot height to fit.

Audio Research resisted using IEC sockets for years for this very reason. There is no better connection than a hard wired power cord.